Principal Engineer, AI & Search Platform

Jobtailor; California (MO); On-site; USD 180,000 - 260,000; Full time

Job summary

Pinterest seeks a senior technical leader to define and drive architecture for Homefeed, Search, and AI Assistant. You will unify signals, models, and features across surfaces, lead large-scale retrieval/ranking designs, and integrate LLMs with the discovery stack.

This role requires deep experience in AI/ML systems, strong collaboration with PM and Data Science, and a track record of architectural transformations.

Qualifications

• 15+ years of industry experience in large-scale systems and/or machine learning.
• Track record of impact in search, recommendations, feeds, or conversational AI.
• Experience as a Principal Engineer, Architect, or equivalent senior technical leader.
• Deep expertise in at least two of: large-scale retrieval and ranking; representation learning; search systems; large language models and generative AI.
• Experience defining and driving multi-year architectural transformations at scale.
• Strong product intuition and experience partnering with PM, Design, and Data Science on ambiguous 0→1 and 1→N product bets.
• Exceptional communication skills.
• Experience mentoring and growing senior/staff engineers and building engineering cultures.
• Bachelor’s degree in computer science or related field.

Responsibilities

• Define the long-term technical strategy and architecture for Homefeed, Search, and AI Assistant, including retrieval, ranking, personalization, and generative experiences.
• Drive a multi-year roadmap unifying signals, features, and models across surfaces.
• Lead large-scale retrieval and ranking system design and adoption.
• Architect LLM and foundation-model integration with the discovery stack.
• Set technical direction for experimentation, measurement, evaluation, offline metrics, online experimentation, and causal inference.
• Provide hands-on technical leadership on high-leverage projects, including component design, design and PR reviews, prototyping, launch risk reduction, and mentoring.
• Partner with Product, Data Science, Research, and Design on technical plans and long-term platform health.
• Raise engineering excellence in reliability, performance, security/privacy, cost efficiency, and operational health.
• Represent Pinterest externally through talks, publications, and partnerships; attract and grow talent.
• Report to Core Engineering leadership and work across Homefeed, Search, and AI Assistant teams.
• Drive long-term strategy, standards, and organizational alignment.
• Deliver durable technical impact through system improvements, model/product outcomes, reduced complexity and operational risk, and leadership growth.

Skills

Large-Scale Retrieval

Ranking Systems

Representation Learning

Search Systems

Large Language Models

Generative AI

Technical Strategy Definition

System Design

Causal Inference

Experimentation Measurement

Mentoring

Communication

Product Intuition

Collaboration

Education

Bachelor’s Degree in Computer Science

Job description

Pinterest seeks a senior technical leader to define and drive architecture for Homefeed, Search, and AI Assistant. You will unify signals, models, and features across surfaces, lead large-scale retrieval/ranking designs, and integrate LLMs with the discovery stack.

This role requires deep experience in AI/ML systems, strong collaboration with PM and Data Science, and a track record of architectural transformations.